Dave's Digital Madness(TM), the next step

uglymusicuglymusic
in Digital
Colin's Linear Power Supply is every bit as good as I hoped. And the Chinese Linear Power Supply driving my server is really good, and will stay unless Colin comes up with another of his fantastic designs - I have talked to him about it, but as far as I know nothing is bubbling away in Colin's Cauldron yet.

So, the next step in Dave's Digital Madness(TM) is to try to further reduce the amount of digital noise in the system by doing some more work right at the start of the music's journey. Currently, it's stored on conventional hard disks in the noisy environment of a Synology NAS. My original plan was to put a linear PSU on the NAS, but since the Raspberry Pi 5 came out, there have been more opportunities to use it as a server.

By putting the music locally on an SSD on my RPi 5 server, the files are removed from all that stuff going on in the Syno. I save myself the cost of a linear PSU, but this solution is actually more expensive. But I like the simplicity. I'm not trying to add sticking plaster to the multipurpose storage I'm currently using.

How am I going to build my new server? I have bought what seems to be a nice case, 3D-printed by a guy on eBay. It'll arrive this week if Postie doesn't lose it (another story). That's purely cosmetic because I hate the case I'm now using for the server, which is one of those red and white jobbies made by Raspberry Pi. I have a fan on the way, then a card to connect an NVME hard disk (the small-format guys that run like fury).

All I'll need to complete the hardware is a 4TB NVME drive. I'm keeping an eye out for a good one at a better discount because these things retail at Β£250 a throw or more. I want a good brand at as much below Β£200 as possible. I'll see. 

I know all that lot will work with Raspberry Pi OS, but I need to run Ubuntu Linux because the latest version of SnakeoilOS is built on it. Do I see an expensive train wreck? I hope not. There's an official version of Ubuntu for the RPi, and similar setups are running successfully, so I'm optimistic.

Does that make sense, or am I going digitally loony?  :s 

Comments

  • AntiCrapAntiCrap
    Hi Dave what voltage and current do you need.
    The kit amp pcb works well as a DC psu I made one for Melvin a few week ago. 

    Best Col
  • uglymusicuglymusic
    edited February 7
    That's a good question. I'll have to check the current demands with the SSD piggybacking on the RPi 5. Voltage is 5V as before.

    Interesting that the kit amp PCB works well for this. How come?

    What is Melvyn using his for, and how is he getting on with it? Maybe he could start a thread here.
  • uglymusicuglymusic
    No case yet, but the fan has arrived.
  • SmiffySmiffy
    uglymusic said:
    That's a good question. I'll have to check the current demands with the SSD piggybacking on the RPi 5. Voltage is 5V as before.

    Interesting that the kit amp PCB works well for this. How come?

    What is Melvyn using his for, and how is he getting on with it? Maybe he could start a thread here.
    Dave, do you have anything like this to monitor voltage & current demand via USB connection?

    https://www.ebay.co.uk/itm/384782166109?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=-4xkiftwsz6&sssrc=4429486&ssuid=MUXnhpQpTTq&var=&widget_ver=artemis&media=COPY
  • uglymusicuglymusic
    No. And that would tell me the current demand for the finished server?
  • SmiffySmiffy
    uglymusic said:
    No. And that would tell me the current demand for the finished server?
    Actually, your server would be fed from wall socket 240v I presume ?
    If so, then Nope.

    If it's fed from Colin's USB power box, then Yes !
  • AntiCrapAntiCrap
    I think it needs 2 psu mine does 12V and 5V about 150W in my case ripple noise etc is less than 1mV pk on both output the SMPSU that came with had 1V ripple on 12V but 1.2V just noise on the 5V yuk
  • uglymusicuglymusic
    AntiCrap said:
    I think it needs 2 psu mine does 12V and 5V about 150W in my case ripple noise etc is less than 1mV pk on both output the SMPSU that came with had 1V ripple on 12V but 1.2V just noise on the 5V yuk
    No, I don't think so. Only 1. There's no power input on the board I have, but I ordered the wrong one, anyway. It doesn't accommodate the disk I need to use - it's a different form factor.

    But I need to make sure. I haven't had time to check it out today. We've been walking Thelonious, taking a friend out for lunch... and the case I'm using for this server project arrived. So I had to take the old case with its fan and heatsink apart and install the RPi and its new fan into the new case.

    Some people build sheds...
  • SmiffySmiffy
    ...Which reminds me - I need to finish my man cave 🀦🏻
  • uglymusicuglymusic
    Smiffy said:
    uglymusic said:
    No. And that would tell me the current demand for the finished server?
    Actually, your server would be fed from wall socket 240v I presume ?
    If so, then Nope.

    If it's fed from Colin's USB power box, then Yes !
    It's a 5V device, run probably from Colin's PSU. I guess what you're saying is to get the server built and running using the Chinese PSU and measure what it's drawing before giving Colin the go-ahead.

    Am I understanding you? Sorry, sometimes I'm a bit slow  ;)  
  • uglymusicuglymusic
    AntiCrap said:
    I think it needs 2 psu mine does 12V and 5V about 150W in my case ripple noise etc is less than 1mV pk on both output the SMPSU that came with had 1V ripple on 12V but 1.2V just noise on the 5V yuk
    Re-reading this, Col, with abacus in hand, are you saying the PSU can deliver 3A max? The RPi 5 standard SMPSU is a 5 amp one. I guess this is where Andy's power measurement doodah comes in.  
  • SmiffySmiffy
    uglymusic said:
    Smiffy said:
    uglymusic said:
    No. And that would tell me the current demand for the finished server?
    Actually, your server would be fed from wall socket 240v I presume ?
    If so, then Nope.

    If it's fed from Colin's USB power box, then Yes !
    It's a 5V device, run probably from Colin's PSU. I guess what you're saying is to get the server built and running using the Chinese PSU and measure what it's drawing before giving Colin the go-ahead.

    Am I understanding you? Sorry, sometimes I'm a bit slow  ;)  
    It's difficult at times to get things across via the written word, I'm probably as much to blame so don't apologise.

    Okay, I think I'm with you now Dave.

    So your RPi (Raspberry Pi) is sent power (normally) from a smps (switched mode power supply) Wall-wart box πŸ‘
    IT has a connection to the RPi via a USB connector.

    Therefore, you can use one of them usb dongles to plug in between Colin's USB Pwr supply and your RPi.

    One question: where do the fan/s get their power from? Is it directly off the RPi board ?
  • uglymusicuglymusic
    Almost there. It's not a SMPS, but a LPSU, like this one: https://www.ebay.co.uk/itm/274957872790

    I bought it because Colin was offline or backed up.

    But when I last saw Colin, we talked about the possibility of getting something better, hence these current (boom, boom) conversations.

    So there's a cable leading from the PSU with a USB-C plug on the end. So I plug the USB-C plug into the meter and get a lead with two male USB-Cs between the meter and the RPi, and I can monitor the power draw.

    The fan draws power from the RPi.
  • SmiffySmiffy
    Gotcha πŸ‘
  • uglymusicuglymusic
    So I’ll get the hardware components and the software together and working, then buy one of those meters and measure the current when I have all the systems and Sonoses playing and the files indexing. I’ll also check current draw while the system is booting. 

    One of those should be the maximum draw. 
  • SmiffySmiffy
    Dave, rather than power the fan off the RPi board, use the smps to power it independently. That way, the fan can't interfere with Colin's pure power supply πŸ˜ŽπŸ‘Œ
  • uglymusicuglymusic
    That’s a good idea. 
  • uglymusicuglymusic
    Did I tell you I ordered the wrong board to connect the drive to the RPi?
  • SmiffySmiffy
    Ooops 🀦🏻
  • AntiCrapAntiCrap
    What a analogue one?
  • uglymusicuglymusic
    Smiffy said:
    Ooops 🀦🏻
    Yeah. I misread 2230 as 2280, and the 4TB drive isn't available in that form factor.
  • uglymusicuglymusic
    AntiCrap said:
    What a analogue one?
    That would be so wrong  :#
  • SmiffySmiffy
    uglymusic said:
    Smiffy said:
    Ooops 🀦🏻
    Yeah. I misread 2230 as 2280, and the 4TB drive isn't available in that form factor.
    Damm !

    So what's the plan now then Batman?
  • uglymusicuglymusic
    edited February 16
    I have all the parts now: Raspberry Pi 5, fan, PSU, PCIe card for M.2 drive, 4TB NVME drive and case. The wrongly purchased board is being returned for a refund.

    If I have time today, I'll assemble it all and see if I can get it to work with my current software set up on an SD card. Boot from the card and see if it can see the NVME drive. 

    If that's OK, I'll put Ubuntu on the NVME drive and install the latest SnakeoilOS. That is probably going to be the most challenging thing, but I'll find out when I get it installed.

    If that all works, I'll think about the fan, and discuss noise shielding with Colin again after that. 

    Phew!
  • uglymusicuglymusic
    And all of this may make absolutely no difference to the overall SQ, of course :s
  • AntiCrapAntiCrap
    It will have faith it either ON or OFF 
  • uglymusicuglymusic
    I think I prefer 1 to 0.
  • uglymusicuglymusic
    edited February 16
    AntiCrap said:
    It will have faith it either ON or OFF 

    I try not to have any expectations, but I must have to spend the time and money.
  • cj66cj66
    A couple of things I found beneficial in my rabbit-hole journey, that I'm not aware of you mentioning...

    1) Galvanic isolation on USB.
    2) Power injection also for USB.

    These work best when using good PSUs like the C14 breed....
  • uglymusicuglymusic
    edited February 16
    Thanks, Chris.
    I'll put them on the list for after I've got the server working.
  • uglymusicuglymusic
    Update: I don't have enough of the right spacers to fit it all into my case. You'll need to hold your breath until next weekend :'(
  • SmiffySmiffy
    uglymusic said:
    And all of this may make absolutely no difference to the overall SQ, of course :s
    So what about your clock reference? πŸ€”
    What or where is it ?
  • uglymusicuglymusic
    Clock reference?
  • SmiffySmiffy
    Yes, every digital system has a master clock reference.
    And every computer system must have a 'heartbeat' (not like Col's turbo turbine thingymabob), including your RPi.

    But I'm alluding in particular to your Dac board. If you're going to make a superior digital system maybe you need to focus on this section? πŸ€“

  • uglymusicuglymusic
    edited February 19
    Good point. But my DAC isn't a board, so no probs there. There's just the board for the NVMe drive, connected to PCIe, the RPi 5 and the fan.
  • SmiffySmiffy
    If you say your Dac isn't a 'board' then where is the D2A convertor?
  • SmiffySmiffy
    You're still using the SMSL M300 Mk2 DAC right ?
  • SmiffySmiffy
    edited February 19
    https://www.amazon.co.uk/Flagship-Decoding-Ultra-high-Ultra-low-Distortion-red/dp/B07PJQDSF2
  • uglymusicuglymusic
    Smiffy said:
    If you say your Dac isn't a 'board' then where is the D2A convertor?
    It isn't an RPi HAT. The D2A converter is in a separate box, away from the RPi. 
  • uglymusicuglymusic
    Smiffy said:
    You're still using the SMSL M300 Mk2 DAC right ?
    Yes.
  • uglymusicuglymusic
    Smiffy said:
    https://www.amazon.co.uk/Flagship-Decoding-Ultra-high-Ultra-low-Distortion-red/dp/B07PJQDSF2
    Yes. A lower-priced DAC, but with an outboard SMPS, which could (and has been) swapped out for a Colin linear one. If you buy a more expensive one, you're stuck with the manufacturer's power supply unless you want to go in for some surgery.
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